Spider Communities of "Yamskaya Steppe" Nature

The Kharkov Entomological Society Gazette 2002(2003) V10 (1-2) P. 99-107

SPIDER FAUNA (ARANEI) AND ASSEMBLAGES OF THE "YAMSKAYA STEPPE" NATURE RESERVE (BELGOROD AREA, RUSSIA) N. Yu. Polchaninova Kharkov National University, Ukraine polchaninva@mail. ru

Introduction The fauna inventory in nature reserves has always been a topical issue. It is especially impor- tant in the steppe reserves that are the only places where the virgin steppes have been preserved. Until recently, the araneofauna of European meadow steppes has not been investigated evenly. The most complete data is given for the "Streletskaya Steppe" (Pichka, 1984 a,b; Polchaninova, 2003) where 160 species were recorded. 84 species are known for the "Kazatskaya Steppe" (Pol- chaninova, 2002) – both parts of the Central-Chermozyom reserve, Kursk Area. The first spider sampling in the "Yamskaya Steppe" was carried out by the members of the Club of young zoolo- gists of Kharkov Pioneer Palace in 1981-1982. The material was identified by the author, and 51 spider species were discovered (Yakushenko at all, 1984). Spiders, as numerous and diverse component of steppe biota, serve a suitable object for monitoring a state of animal communities of various habitats under the influence of different conservation managements. Material and Methods The "Yamskaya Steppe" is part of the "Belogorye" Nature Reserve and is situated in the Central Forest-Steppe in the Central Russian upland (Milkov, 1950). The main part of its terri- tory is occupied by meadow steppe, oak forest being located in a ravine. The steppe is divided into several parts with different mowing regime. There are un-mowed (i.e. strictly protected), periodically mowed and annually mowed plots. We designated those as UMS, PMS and AMS, respectively. PMS-1 was not mowed in 2000-2002, PMS-2 was mowed in that period, PMS-3 was not mowed only in 2002. UMS-1, PMS-1, PMS-2 are situated on the plateau, UMS-2 occu- pies the plateau and the upper part of a ravine neibouring with an oak forest belt, PMS-3 lies on the north – facing ravine slope and in the bottom. The material was collected in May-September 2001– 2002 by conventional methods: net sweeping, pitfall traps, quadrate sampling, and hand collecting. The total of 12.990 individuals represented 154 spider species from 18 families were collected. To this list, Eresus niger Oliv. (Eresidae) should be added. It was found by A.V. Prissy on achalk slope (personal communication). The list is given according to Mikhailov, 1997. Results and Discussion Linyphiidae family is prevailing among the spiders inhabiting "Yamskaya Steppe" reserve. That is typical of the most of local faunas in the forest-steppe. Theridiidae and Araneidae are nearly twice as poor, 4 families account for 8-10%, and the others make up only 1-3% (table 1). Such a hierarchical structure is determined by Linyphiidae occurring in a forest ravine. In the un- mowed steppe the role of Linyphiidae is lower, and in the mowed one it falls out of the dominant complex. In the steppe habitats, there is no significant difference in number of dominant families. In UMS this complex consists of Linyphiidae, Theridiidae, Araneidae, Lycosidae, in PMS the first two families are replaced by Gnaphosidae and Theridiidae. Table1. Species composition of spider families if forest and steppe habitats. N – species number Steppe Forest ravine glades. under the Total Families Un-mowed mowed Total Total forest edges canopy N % N % N % N % N % N % N % MIMETIDAE 1 1 1 1 1 1 1 1 0 0 1 1 1 1 THERIDIIDAE 13 15 6 8 14 13 6 6 8 12 8 7 19 12 LINYPHIIDAE 16 17 5 8 17 16 24 23 24 35 31 26 35 23 TETRAGNATHIDAE 1 1 0 0 1 1 4 4 4 6 4 3 5 3 ARANEIDAE 12 14 10 13 12 12 16 15 6 9 16 14 18 12 LYCOSIDAE 9 10 11 15 12 12 8 8 5 7 9 8 12 8 PISAURIDAE 1 1 1 1 1 1 1 1 0 0 1 1 1 1 AGELENIDAE 2 2 2 3 2 2 2 2 1 1 2 2 2 1 HAHNIIDAE 0 0 0 0 0 0 1 1 1 1 1 1 1 1 DICTYNIDAE 2 2 1 1 2 2 2 2 2 3 2 2 3 2 LIOCRANIDAE 3 3 1 1 3 3 2 2 1 1 2 2 3 2 CLUBIONIDAE 3 3 4 5 4 4 3 3 1 1 3 3 5 3 GNAPHOSIDAE 7 8 11 15 11 11 11 10 2 3 11 9 15 10 ZORIDAE 1 1 1 1 1 1 2 2 1 1 2 2 2 1 HETEROPODIDAE 1 1 1 1 1 1 1 1 1 1 1 1 1 1 PHILODROMIDAE 3 3 3 4 3 3 4 4 1 1 4 3 5 3 THOMISIDAE 6 7 9 12 9 9 9 8 5 7 10 8 13 8 SALTICIDAE 8 9 7 9 10 10 9 8 5 7 10 8 13 8 Species in total 89 100 75 100 104 100 106 100 68 100 118 100 154 100

Nearly all species found are characterized by wide areas. These are holarctic, palearctic, west-central palearctic and European species. It is worth mentioning finds of a Eurasian steppe species Gnaphosa taurica and trans-Eurasian subboreal Eresus niger that are rare for the forest- steppe. Araneofauna of forest habitats is always a little richer than that of steppe ones. 118 spider species were found in the forest ravine while 104 species occurred on the steppe plots. As in all investigated nature reserves, spider species composition is more diverse in un-mowed steppe than in mowed one. However we did not find any species associated with the UMS only (here and further single finds are not considered under in the analysis of habitat distribution). An in- crease of species diversity is stipulated by the presence of forest elements that can survive in more stable and moist conditions of UMS. Ta b l e 2 . Habitat distribution of the spiders of ‘Yamskaya steppe’ Abbreviation: 1- species, 2 - UMS, 3 - PMS-1, 4 - PMS-2, 5 – ravine bottoms, 6 - belt of oak trees , 7 - edges of forest ravines, 8 - glades, 9 – forest, under the canopy 1 2 3 4 5 6 7 8 9 MIMETIDAE Ero furcata Villers + + – – – – + – THERIDIIDAE Achaearanea lunata (Cl.) – – – – – – – + A. simulans (Thor.) + – – – – – – + Crustulina guttata (Wider) + – – – + + + + C. sticta (O. P.-C.) – + – – – – – – Dipoena tristis (Hahn) + – – – – – – – Enoplognatha latimana Hippa et + – – – – – – – E. ovata (Cl.) + – – – + + + + Episinus angulatus (Bl.) + – – – – – – – Euryopis flavomaculata (C. L.K.) + + + + + + + + Robertus arundineti (O. P.-C.) + – – – – – – – R. lividus (Bl.) + + – – – – – – Steatoda bipunctata (L.) * – – – – – – – – S. castanea (Cl.) * – – – – – – – – S. phalerata (Panzer) – + + – – – – – Theridion bimaculatum (L.) + + + + + + + + T. impressum L. K. + + + + + + + + T. mystaceum L. K. + – – – – – – – T. pinastri L. K. + – – – – – – – T. varians (Hahn) – – – – – + + + LINYPHIIDAE Abacoproeces saltuum (L. K.) – – – – – + – + Agyneta rurestris (C. L. K.) + + + – – – – + A. saxatilis (Bl.)1 – + – – – – – – Centromerus incilium (L. K.) + – – – – – – – C. sylvaticus (Bl.) – – – – + – – + Ceratinella brevis (Wider) + – – – – + – + C. scabrosa (O. P.-C.) – – – – – – + + Ceratinopsis stativa (Sim.) – – – – – + – – Diplocephalus picinus (Bl.) + – – – + – – + Diplostyla concolor (Wider) – – – – – – + + Entelecara flavipes (Bl.) + – – – + + + – Erigone dentipalpis (Wider) + – – – – – – – Floronia bucculenta (Cl.) – – – – – + + + Gonatium paradoxum (L.K.) + – – – + + + + Gongylidium rufipes (L.) + – – – – + + + Helophora insignis (Bl.) – – – – – – – + Hylyphantes nigritus (Sim.) – – – – + + + + Lepthyphanthes flavipes (Bl.) – – – – – – – + Linyphia hortensis Sund. – – – – + – + + L. tenuipalpis Sim. – – – – + + – – L. triangularis (Cl.) + – – – + + + + Macrargus multessimus (O. P.-C.) – – – – – – – + Maso sundevalli (Westr.) – – – – + + + + Microlinyphia pusilla (Sund.) + + + + – – + – Microneta viaria (Bl.) – – – + + + + + Minicia marginella (Wider) + – – – – + – + Neriene clathrata (Sund.) + – – + + + + + Oedpthorax apicatus (Bl.) + – – – – – – – Pelecopsis radicicola (L. K.) – – – – – – + – Stemonyphantes lineatus (L.) + + + – – + – – Trematocephalus cristatus – – – + – + – – (Wider) Troxochrus scabriculus (Westr.) – – – – – + + + Walckenaeria atrotibialis O. P.-C. + – – – – – – – Walckenaeria furcillata (Mg.) – – – – – – – + W. nudipalpis (Westr.) – – – – – – + + 2 Micryphantinae gen. sp. 1 + + + – + + + + TETRAGNATHIDAE Metellina segmentata (Cl.) + – – – + + + + Pachygnatha degeeri Sund. – – – + – – – – P. listeri Sund. – – – – – + + + Tetragnatha montana Sim. – – – – – – + + T. pinicola L. K. – – – – + + + + ARANEIDAE Agalenatea redii (Scop.) + + + + + + – – Araneus alsine Walck. – – – – – – + + A. angulatus Cl. – – – – – + + – A. diadematus Cl. + + + + + + + + A. marmoreus Cl. – – – – + + + + A. quadratus Cl. + + + + + + + – Araniella cucurbitina (Cl.) – – – – + + + – Argiope bruennichi Scop. + + + + + + + – Cercidia prominens (Westr.) + + + + – – + + Cyclosa conica (Pall.) + + – + + + + + C. oculata (Walck.) + + – – – – – – Gibbaranea bituberculata – – – – – + + – (Walck.) Hypsosinga pygmaea (Sund.) + + – – – – – – H. sanguinea (C. L. K.) + + + + + + + – Larinioides patagiatus (Cl.) + – – + + + + –

1 erroneous identification. the specimen belongs to M. simplicitarsis (Simon, 1884) (NP, pers. com. 2011). 2 later it was described as Russocampus polchaninovae Thanasevitch, 2004 Mangora acalypha O. P.-C. + – – + + + + + Neoscona adianta (Walck.) + + + + + + + – Zilla diodia (Walck.) – – – – – – + – LYCOSIDAE Pardosa agrestis Westr. – – – – – + – – P. lugubris (Walck.) + + – + + + + + P. palustris (L.) + + + + + + + – P. pullata (Cl.) – + – + – – – – Tarentula aculeata (Cl.) + + + + + + + – T. pulverulenta (Cl.) + + + + + – – – T. sulzeri Pavesi – + – – + + + – T. trabalis (Cl.) + + + + + + + + Tricca lutetiana (Sim.) + + + + + + + + Trochosa ruricola (De Geer) + – + – – – – + T. terricola Thor. + + + + + + + + Xerolycosa miniata (C. L. K.) + + + + – – – – PISAURIDAE Pisaura mirabilis (Cl.) + + – – + + + – AGELENIDAE Agelena gracilens C. L. K. + + + + + + + – A. labyrinthica (Cl.) + + + + + + + + HAHNIIDAE Hahnia ononidum Sim. – – – – + – + + DICTYNIDAE Dictyna arundinacea (L.) + + + + + + + + D. uncinata Thor. + – – + + + + + Nigma flavescens (Walck.) – – – – + – – – LIOCRANIDAE Agroeca brunnea (Bl.) + – – – + + + + A. cuprea Mg. + – + + + – – – A. lusatica (L. K.) + – – + + + – – CLUBIONIDAE Cheiracanthium erraticum Walck. + + + + + + + – Ch. punctorium Villers + + – + + + + – Clubiona caerulescens L. K. – – – – – + + + C. diversa O. P.-C. – + – + – – – – C. neglecta O. P.-C. + + + + – – – – GNAPHOSIDAE Callilepis nocturna L. – – – – – – + – Drassodes pubescens (Thor.) + + + + + + + – Drassylus praeficus (L. K.) + + + – + – – – D. pusillus C.L.K. + + + + + + + + Gnaphosa taurica Thor. – – + – – – – – Haplodrassus signifer C.L.K. + + + + + + + – H. silvestris (Bl.) – – – – + + + + H. umbratilis (L.K.) – – – – – – + – Micaria formicaria (Sund.) + + – + + + + – M. pulicaria (Sund.) – – – – + + – – Zelotes apricorum (L.K.) – + – – – + + – Z. electus (C.L.K.) – + – + – – – – Z. latreillei (Sim.) + + + + – + + – Z. longipes (L.K.) – – + – – – – – Z. subterraneus (C.L.K.) + + – + + – + – ZORIDAE Zora nemoralis (Bl.) – – – – + + – – Z. spinimana (Sund.) + + – + + + + + HETEROPODIDAE Micrommata roseum (Cl.) + + – + + + + + PHILODROMIDAE Philodromus cespitum (Walck.) + – – – + + + + Thanatus arenarius Thor. – + – – + + – – T. formicinus (Cl.) + + + + + + + – T. striatus C. L. K. – – – – + – – – Tibellus oblongus (Walck.) + + + + + + + – THOMISIDAE Misumena vatia (Cl.) + + – + + + + + Misumenops tricuspidatus (Fabr.) + + – – + + + + Ozyptilla atomaria (Panzer) + + + + + – – – O. claveata Walck. – – – – – + – – O. praticola (C. L. K.) – – – – + – – + O. scabricula (Westr.) – + + – – – – – Xysticus cambridgei (Bl.) – – – – + + + + X. cristatus (Cl.) + + + + + + + – X. kochi Thor. – – + + – – – – X. lanio C. L. K. – – – – – + + – X. robustus (Hahn) – + + + + + – – X. striatipes L. K. + + + + – + – – X. ulmi (Hahn) + + – + + + + + SALTICIDAE Ballus depressus (Walck.) + – – + – + + + Bianor aurocinctus Ohl. + – – – – – – – Euophrys frontalis Walck. + – – – – – – – Evarcha arcuata (Cl.) + + + + + + + + E. falcata (Cl.) – – – – – + + + E. laetabunda (C.L.K.) + + + + + + + – Heliophanus auratus C.L K + + + + + + + + H. cupreus (Walck.) – – – + + + + + H. flavipes (Hahn) + + + + + + – – Marpissa pomatia (Walck.) + + + + + + + – Phlegra fasciata (Hahn) – – + + – + – – Pseudicius encarpatus Walck. – – – – – – – + Talavera aequipes (O. P.-C.) – – + – – – – – Species in total 89 68 51 63 80 91 88 68 Footnote * – species found in humain dwellings

(Crustulina gutttata, Enoplognatha latimana, E. ovata, Ceratinella brevis, Diplocephalus picinus, Gonathium paradoxum, Gongylidium rufipes, Minicia marginella, Metellina segmentata, Agroeca brunnea, Philodromus cespitum и др. Исключительно в косимой степи встречаются Steatoda phalerata). 3 species (Steatoda phalerata, Agyneta simplicitarsis, Ozyp- tila scabricula) occurred in the mowed steppe exclusively. They do not belong to genuine steppe species, and in the steppe zone they are recorded in all habitats (O. scabricula) or only in intra- zonal ones. The conditions of mowed steppe in the forest-steppe zone turned out to be optimal for them. Thus, the local steppe fauna has a low rate of species specificity. Besides the 3 abovementioned species, Hypsosinga pygmaea, Clubiona neglecta, C. diversa, Gnaphosa taurica, Zelotes electus, Z. longipes occurred only in this habitat, making up 8.6% of the steppe fauna. In addition, 11 species were found by one specimen each. Forest sites are inhabited by a higher number of stenotopic species. First of all, ombro- and mesophilers occurring under the canopy (Achaearanea lunata, Theridion varians, Abacoproeces saltuum, Diplostyla concolor, Ceratinella scabrosa, Helophora insignis, Lepthyphantes flavipes, Linyphia hortensis, Maso sundevalli, Troxochrus scabriculus, Hahnia ononidum, Pachygnatha listeri, Clubiona caerulescens), and photophilers preferring glades and forest margins (Floronia bucculenta, Hylyphantes nigritus, Tetragnatha montana, T. pinicola, Araneus angulatus, A. alsine, A. marmoreus, Araniella cucurbitina, Gibbaranea bituberculata, Xysticus cambridgei, X. lanio, Evarcha falcata ) – 25 species, 21%. The others are mainly polytopic and inhabit different habitats. This explains a high degree of faunistic similarity of the steppe and forest araneofauna (Jakkard I = 70%). Spider communities are less homogeneous than species composition and alter even with in- significant changes of relief, light intensity and weather conditions. That may be observed in every habitat. There were 64 species found in the UMS-1, and 73 species in the UMS-2. The proximity of the forest habitats determines higher species diversity of the second plot. It is here that species untypical for steppes occur (Achaearanea simulans, Enoplognatha spp., Centromerus incilium, Neriene clathrata, Linyphia triangularis, Agroeca lusatica), and in this very plot forest-edge species are frequent (Mangora acalypha, Evarcha arcuata, Pardosa lugubris). In other respects, the individual number and hierarchical structure of spider communities on these two plots differ insignificantly, and change with the appearance and maturity of dominant species. Thus, the dominant structure of spiders in different years changed significantly, though hav- ing a common tendency. It is also relevant to a general dynamics of spider abundance in the herb and litter. In the ground stratum this dynamics is determined by development period of Taren- tula trabalis. In May 2002 it made up 71-80%, while in 2002 it was 56-67%. The abundance of mature individuals decreased by August (16-18%), while the range of juvenile forms increased in this month up to 50-54%. The number of Trochosa terricola, on the contrary, rose from May to August. Haplodrassus signifer and Drassodes pubescens dominated also over the end of June and early July, but in 2002 the latter was replaced by O atomaria and X. robustus in the UHS-1. As we can see, spider guilds in the litter were still less stable than in the herb. Naturally, seasonal dynamics of spider diversity in the mowed steppe depends on the dates of mowing (fig.1). In the PMS-2 and PMS-3, the lack of the last year's dry stalks on which Agalenates redii and Dictyna arundinacea prefer making their webs, results in total decline of individual number and monodominance of Araneidae (55-70%). If the steppe is moved in July, there can be found only a few specimens of Xysticus, Tibellus, Hypsosinga. While the growing herbage is being settled, spider density in August achieves the value of June, exceeding it in Sep- tember. A 40 2002 40 2001 30 30 f 20 20

10 10 species number o number 0 0 1234 56789 Month Month B 50 2001 40 2002 35 40 30 30 25 20 20 15 spec/sample

Number ind of 10 10 5 0 0 5678 56789 Month Month

Fig. 1. Seasonal dynamics of species richness (A) and spider abundance (B) in steppe herbage

Habitat distribution of two dominant Araneidae species is of great interest. Neoscona adianta is typical of steppes and is a main dominant in all the southern nature reserves. Araneus quadrarus is rare in forbgrass steppes it is a common inhabitant of forest edges, meadows and meadow steppe in the forest-steppe zone. In 2002, the percentage ratio of Araneus:Neoscona was: in the UMS 11:25, in the PMS on the plateau 18:35, on the ravine slope 16:11, respectively. In the ravine bottom, no specimens of Neoscona were found. In drier and hotter 2002, A. quadratus was rare on the plateau and common in ravines only. The density of surface dwelling spiders in the steppe litter, even in the MS-1, was very low; all species were recorded as singletons, seasonal changes being difficult to determine (fig. 2). In contrast to the un-mowed steppe, Tarentula trabalis was not the prevailing dominant among wandering spiders. In May-July it made up not more than 24-33%, and was absent from some samples. Along with it there was a close species T. aculeata found, more numerous in 2002. Haplodrassus signifer was a constant dominant, but we could not find any regularity in its habitat distribution. 50 45 АЗС-1.1 40 35 АЗС-1.2 2 30 25

spiders/m 20 АЗС-2.1 15 10 АЗС 2.2 5 0 56789 ПКС-1.2 Months Fig. 2. Seasonal dynamics of spider density in steppe litter 1.1., 2.1. – year 2001; 1.2, 2.2 – year 2002 АЗС - Strictly protected steppe, ПКС - steppe under mowing regime (PMS-1)

In the whole, dominant complexes in the mowed and un-mowed steppe consisted of the same species, though in different ratio. A mean number of spiders in herb layer of the UMS and MS was similar (21– 27 specimens/sample), declining on the plots mowed within the years of investigation (10– 14 spec.) A dynamics density in pitfalls also was higher in the UMS than in MS with the excep- tion of a plot in the bottom of a mowed ravine. It’s interesting to characterize spider communities of detached trees in the steppe. They were affected by a tree kind and a distance from the forest. Oaks were densely settled then pear trees. In June-July they were all covered up to the top with juvenile A. diadematus webs. We have never observed such a high dendrobiont density in any of steppe reserves. A month later, the number of spiders reduced sharply. A. diadematus occurred mainly in the lower layer together with L. ocellatus and N. adianta. Agelena labyrinthica and A. gracilens concentrated in herb under the canopy (2-4 webs/m2. They also inhabit open steppe but prefer vegetation under the trees. Oak trees grew only near the forest ravine while pear trees were scattered throughout the terri- tory. The number of species in their canopy reduced with the distance from the forest, and mar- ginal trees were standing without nets. As early as May the number of spiders and species abundance in the forest habitats were higher than in steppe. D. arundinacea and Araneidae were also dominants but their number was lower, and the third dominant, normally juv. M. acalypha, was present. On the margin of the belt of oak trees, an outbreak of A. bruennichi was recorded in July 2002. Perhaps, it was connected with the previous mowing of the adjacent steppe plot from where the remaining spiders moved to the edge. This big orb-web spider inhabits medium grass layer and is typical of the steppe herb but not very frequent. According to our data, the number of spiders in the forest herb, both under the canopy and on the edges, increases gradually by the end of the growing season due to abundance of the late summer species and youth of the early spring ones. In 2002, we monitored this tendency in glades and on edges. In 2002, the dynamics curve was atypical with falls in June and August (fig 3). Except the belt of oak trees, mean number of spiders in hortobium in the years 2001, 2002 differed insignificantly. It was the highest in the glades - (51-44 spec./sample), lower on forest edges (35-44 spec/sample) and in UMS (25-29 spec/sample), and the lowest in MS (9- 14 spec./sample). species richness almost in all habitats was the highest in June and went down gradually to September (fig. 1, 3). In dynamic of hortobiont spider number, we managed to find only one regularity – higher figures in May 2002 for all the habitats. In other respects, we did find any common tendencies in number changes. 60 2001 35 2002 50 30 40 25 20 30 15 Species 20 10 10 5 0 0 5678 56789 Months Months

100 2001 60 2002

80 50 40 60 30 40 20

specimens/sample 20 10

0 0 5678 56789 Months Months

Fig. 3. Seasonal dynamics of species richness (A) and specimen number (B) of spiders in the herbage of forest habitats On the base of the data obtained, it’s possible to distinguish some characteristic peculiarities of the spider fauna and communities of ‘Yamskaya Steppe’. Firs of all, it’s an extremely high abundance of Tarentila trabalis that never occurs so frequently in other steppe reserves; low number of T. pulverulenta, and the absence of Pardosa riparia, dominant number one in meadow steppe of ‘Streletskaya steppe’, the nearest to ‘Yamskaya’. Second, it’s a relatively low number of species of the genus Pardosa. As a rule, in light open forests and on forest in the forest-steppe, P. lugubris makes up 70–90 % of spiders while here its share didn’t exceed 15– 25 %,and only in the belt of oak trees it reached 48 %. It’s worth mentioning high population of the canopies and herbadge under detached trees in the steppe, and Agelena labyrinthica and A. gracilens accumulation under them. In ‘Streletskaya’ and ‘Kazatskaya Steppe’ we didn’t find them however V. Pichka (1984a, b) had referred then as mass species. Abundance of Neoscona adianta, rare in ‘Streletskaya steppe’ and common ‘Kazatskaya’ high number ofHeliophanus flavipes and Clubiona pseudoneglecta, presence of Xysticus striatipes make the local fauna of this nature reserve with the araneofauna genuine steppes. On the other hand, Araneus quadratus dominance and a large amount of Euryopis flavomaculata, Marpissa pomatia, Theridion bimaculatum, Evarcha arcuata, Cheiracanthium punctorium are distinguishing features of the araneofauna of meadow steppes.

REFERENCES Ганнибал Б К., Калибернова Н. М. Повторная инвентаризация растительного покрова «Ямской степи» (заповедник «Белогорье») через 25 лет: первые итоги // Эталонные степные ландшафты: проблемы охраны, экологической реставрации и использования: Материалы 3 междунар. симп., Оренбург, 16–20 июня 2003 г. – Оренбург, ИПК «Газпромпечать», 2003. – С. 139–142. К фауне и экологии насекомых и пауков Ямского участка Центрально-Черноземного государственного заповедника / Б. М. Якушенко, В. Н. Грамма, А. В. Захаренко и др. // Эколого-фаунистические исследования Центральной Лесостепи европейской части СССР. – М.: ЦНИЛ Главохоты РСФСР, 1984. – С. 54–61. Мильков Ф. Н. Лесостепь русской равнины. – М.: Изд–во АН СССР, 1950. – 297 с. Михайлов К. Г. Каталог пауков территорий бывшего Советского Союза (Arachnida, Aranei). – М.: Зоол. музей МГУ, 1997. – 416 с. Полчанинова Н. Ю. К изучению фауны пауков Казацкого участка Центрально-Черноземного заповедника // Изучение и охрана природы лесостепи: Материалы науч.-практ. конф., посв. 120-летию со дня рождения В. В. Алёхина, Курская обл., пос. Заповедное, 7 января 2002 г. – Тула, 2002. – С. 111–112. Полчанинова Н. Ю. Изменение аранеофауны Стрелецкого участка Центрально-Черноземного заповедника за 17 лет. Степи Северной Евразии // Эталонные степные ландшафты: проблемы охраны, экологической реставрации и использования: Материалы 3 междунар. симп., Оренбург, 16–20 июня 2003 г. – Оренбург, ИПК «Газпромпечать», 2003. – С. 403–405. Пичка В. Е. К фауне и экологии пауков Центрально-Черноземного заповедника // Фауна и экол. паукообразных. – Пермь: Пермск. ун–т, 1984 а. – С. 68–77. Пичка В. Е. О фауне и экологии пауков Центрально-Черноземного заповедника // Эколого-фаунистические исследования Центральной Лесостепи европейской части СССР. – М.: ЦНИЛ Главохоты РСФСР, 1984 б. – С. 65–75. Харьковский национальный университет им. В. В. Каразина Поступила 02.08.2003

UDC 595.44:591.9 (470.325)

N. YU. POLCHANINOVA

SPIDER COMMUNITIES OF THE ‘YAMSKAYA STEPPE’ NATURE RESERVE (BELGOROD REGION, RUSSIA)

Kharkov National University

SUMMARY

A total, ca 12 990 individuals, representing 154 spider species and 18 families were collected from steppe and forest habitats in the ‘Yamskaya steppe’. Most species are habitat generalists commonly occuring in the forest- steppe zone, stenotopic steppe species comprise only 10 % of the fauna, the forest ones attain 20 %. This results in a very high interhabitat faunistic similarity (Jaccard’s Index = 70 %). The highest spider abundance in herb layer and the richest species composition were recorded in the forest glades. These indices decreased in range forest edges, un-mowing steppe, mowing steppe. This local araneofauna differs from the other faunas of the virgin meadow steppes by the great number of Tarentula trabalis, the absence of Pardosa riparia, and a less quantity and diversity of Pardosa species. With the high abundance of Neoscona adianta, presence of Xysticus striatipes, higher quantity of Heliophanus flavipes and Clubiona neglecta the araneofaune of the ‘Yamskaya steppe’ approaches the true steppe type. On the other hand, dominant Araneus quadratus and numerous Euryopis flavomaculata, Marpissa pomatia, Theridion bimaculatum, Evarcha arcuata, Cheiracanthium punctorium are typical of the meadow steppes. 3 figs, 2 tabs, 8 refs.